Veneer peeling apparatus

ABSTRACT

The invention relates to a peeling station with means for rounding a block by peeling and means for producing veneers from the block by peeling The peeling station comprises a frame assembly provided with a rounding segment having first roller elements for accommodating and centering as well as rotating a block and a first knife element for peeling the block to become substantially circular in cross-section during its rotating motion; an interim storage segment for accommodating a rounded block; and a veneer peeling segment having second roller elements for accommodating and rotating the rounded block coming from the interim storage and a second knife element for peeling veneers from a block during its rotating motion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from and the benefit under 35 U.S.C.§119 of Finnish Patent Application No. 20115122, filed Feb. 9, 2011, inthe Finnish Patent Office, which is hereby incorporated herein byreference in its entirety.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present invention relates to a peeling station with means forrounding a block by peeling and means for producing veneers from theblock by peeling.

2. Description of Related Art

The prior art describes various rounding lathes for processing woodblocks in an effort to remove the protruding spots of their outercircumference and to make blocks as circular as possible incross-section. One such prior known rounding lathe is disclosed in U.S.Pat. No. 4,554,958, wherein the rounding lathe is constructed as aspindleless lathe. It discloses two fixed upper rollers mounted on acommon shaft for synchronized rotation. Below each upper roller isprovided two movable rollers adapted to rotate in synchronism with thefixed rollers.

There are previously known spindleless veneer lathes in the prior art,such as for example a veneer lathe described in U.S. Pat. No. 4,781,229.It features a fixed roller and two movable rollers adapted to be movablealong a first and a second plane. This solution enables the anglebetween a lathe knife and a block to be controlled continuously.

The rounding lathe and the veneer lathe are typically implemented asseparate pieces of equipment usually with an interim storage for roundedblocks therebetween.

SUMMARY OF THE DISCLOSURE

An objective of the present invention is to provide an improved peelingstation with a capability of effectively integrating properties of arounding lathe and a veneer lathe. In order to attain this objective, apeeling station of the invention is characterized in that the peelingstation comprises a frame assembly provided with a rounding segmenthaving first roller elements for accommodating and centering as well asrotating a block and a first knife element for peeling the block tobecome substantially circular in cross-section during its rotatingmotion; an interim storage segment for accommodating a rounded block;and a veneer peeling segment having second roller elements foraccommodating and rotating the rounded block coming from the interimstorage and a second knife element for peeling veneers from a blockduring its rotating motion.

The solution according to the invention comprises a single frameassembly, having in an effective manner integrated therein a roundingsegment and a veneer peeling segment, between which is an interimstorage for the rounded block. The rounding segment is provided withmeans for bringing the first roller elements in a mechanicallypositively driven manner to center a block, and with auxiliary spindlescapable of being set against the ends of a block after centering theblock for securing the block in its centered position. This is aneffective way of ensuring the retainment of a block in its centeredposition during a rounding process. The roller elements are adapted tobe released from positively driven mechanical operation once theauxiliary spindles have been set in position, and provided withindependent suspension such that, after being released from positivelydriven operation, said rollers are in a spring-loaded contact againstthe block's outer surface. The use of auxiliary spindles provides arelatively simple roller configuration, wherein one and the same set ofrollers first handles mechanically the centering of a block and, oncethe auxiliary spindles have been attached, the rollers are released frompositively driven mechanical operation, after which the block rotationis carried out by said auxiliary spindles.

The apparatus is further provided with measuring instruments formeasuring the diameter of a block on its way out of the roundingsegment, and with means for feeding the measurement data to controlmeans for the veneer peeling segment's roller elements. Thereby, theveneer peeling segment can be preset for a condition ready to receivethe incoming block for a higher-speed operation of the veneer peelingsegment.

The apparatus according to the invention is capable of providing a highcapacity at low working speeds by virtue of concurrently occurringrounding and veneer peeling processes.

The apparatus according to the invention is preferably constructed as acompact portable unit which can be transported to various work sites,such as e.g. directly to a logging site. The apparatus can be in amounted position e.g. on top of a carriage transported by a truck.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

The invention will now be described more closely with reference to theaccompanying drawings, the sole FIG. 1 of which shows one preferredembodiment of the invention in a schematic view of principle.

DETAILED DESCRIPTION OF THE DISCLOSURE

The present disclosure now will be described more fully hereinafter withreference to the accompanying drawings, in which some, but not allaspects of the disclosure are shown. Indeed, the disclosure may beembodied in many different forms and should not be construed as limitedto the aspects set forth herein; rather, these aspects are provided sothat this disclosure will satisfy applicable legal requirements. Likenumbers refer to like elements throughout.

A veneer peeling station 1 shown in FIG. 1 comprises a rounding segment20 provided with a dispenser 7 for incoming blocks 2 and with a detent 8for the dispenser. The rounding segment has rounding rollers 11 linkedby way of a bracket member 12 to an actuator 13, e.g. to a pneumaticcylinder. The rounding rollers are capable of being coupled mechanicallywith each other, e.g. by means of a centering wheel (not shown) providedwith suitable guide slots (evolvent curves), by placing e.g. theprotruding ends of the rounding rollers' axles in said guide slots andby turning the centering wheel so as to have the roller positivelydriven to a substantially equal distance from the axial center line ofthe block. A block presently in the rounding segment is indicated byreference numeral 3. After centering, the block ends are grabbed byauxiliary spindles 17, followed by releasing the rounding rollers 11from positive drive for bringing the same in an independentlyspring-loaded manner against a surface of the block 3. Each roundingroller is preferably provided with a freewheel clutch. What isaccomplished by this is that, at the initial stage of a roundingprocess, the rollers furthest away from the center of a block aredriving the block rotationally while the closer ones are rotatingfreely. During the rotating motion of a block, a knife mounted on aknife holder 16 removes irregularities of the block's outercircumference as well as makes the block sufficiently circular for theactual lathe work. The rounding segment is preferably provided withmeasuring instruments (not shown) capable of detecting a diameter of theblock 3 on its way out of the rounding segment. In practice, the blockdiameter data is obtained as knife holder beam location data at the endof rounding and this diameter data is handed over to control means ofthe veneer peeling segment's roller elements 10. Thereby, the veneerpeeling segment can be preset for a condition ready to receive theincoming block for a higher-speed operation of the veneer peelingsegment. This veneer peeling segment 21 is accommodated in the sameframe assembly as the rounding segment 20 and includes roller elements10, along with their actuators 14, possibly comprising e.g. pneumaticcylinders, for rotationally driving a block 5. In addition, the veneerpeeling segment has its own knife holder 15 along with its veneerpeeling knife In the apparatus according to the invention, downstream ofthe veneer peeling segment is preferably located a veneer sheet cutter6. Moreover, between the rounding segment and the veneer peeling segmentis provided an interim storage 22 for rounded blocks 4. The block 5 isconveyed from the interim storage into the veneer peeling segment e.g.by means of a swivel arm 9. In connection with the interim storage 22are preferably provided e.g. sawing or cutting members for calibratingthe ends of the rounded block 4 to a desired dimension, i.e. forcalibrating the length of a block.

The above-described embodiment has been illustrated in a highlyschematic manner for making essential features of the inventionunderstandable, nor does it include all of the elements necessary foroperation of the apparatus and readily appreciated by a person skilledin the art, such elements being e.g. drive units for the rollers 11, 10,which may comprise e.g. a gear motor or a chain drive, or e.g. feedingelements for supplying blocks to the apparatus or conveying elements forcarrying the cut veneer sheets away from the apparatus for furtherprocessing.

Many modifications and other aspects of the disclosures set forth hereinwill come to mind to one skilled in the art to which these disclosurespertain having the benefit of the teachings presented in the foregoingdescriptions and the associated drawings. Therefore, it is to beunderstood that the disclosures are not to be limited to the specificaspects disclosed and that modifications and other aspects are intendedto be included within the scope of the appended claims Although specificterms are employed herein, they are used in a generic and descriptivesense only and not for purposes of limitation.

1. A peeling station provided with means for rounding a block by peelingand means of producing veneers from the block by peeling, wherein thepeeling station comprises a frame assembly provided with a roundingsegment having first roller elements for accommodating and centering aswell as rotating a block and a first knife element for peeling theblock, such that the block becomes substantially circular incross-section during rotating motion thereof; an interim storage segmentfor accommodating a rounded block; and a veneer peeling segment havingsecond roller elements for accommodating and rotating the rounded blockcoming from the interim storage and a second knife element for peelingveneers from the rounded block during rotating motion thereof.
 2. Apeeling station as set forth in claim 1, wherein the rounding segment isprovided with means for bringing the first roller elements in amechanically positively driven manner to center the block; that therounding segment has auxiliary spindles capable of being set against theends of the block after centering the block for securing the block inits centered position; that the first roller elements are adapted to bereleased from positively driven mechanical operation once the auxiliaryspindles have been set in position; and that the roller elements areprovided with independent suspension such that, after being releasedfrom positively driven operation, said rollers are in a spring-loadedcontact against an outer surface of the block.
 3. A peeling station asset forth in claim 1, wherein the frame assembly is further providedwith a cutter member downstream of the veneer peeling segment forcutting a veneer coming from the veneer peeling segment into veneersheets.
 4. A peeling station as set forth in claim 1, wherein theinterim storage includes associated elements for calibrating the ends ofthe rounded block to a desired dimension.
 5. A peeling station as setforth in claim 1, wherein the rounding segment includes associatedmeasuring instruments for measuring a diameter of the block on its wayout of the rounding segment, and means for feeding the measurement datato control means of the roller elements of the veneer peeling segment.6. A peeling station as set forth in claim 1, wherein the peelingstation is configured as a compact portable unit capable of beingtransported to various work sites.